patch 9.1.0771: completion attribute hl_group is confusing

Problem:  Currently completion attribute hl_group is combined with
          all items, which is redundant and confusing with kind_hlgroup
Solution: Renamed to abbr_hlgroup and combine it only with the abbr item
          (glepnir).

closes: #15818

Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/dumps/Test_pum_highlights_12.dump b/src/testdir/dumps/Test_pum_highlights_12.dump
index a0d2b49..c7c2001 100644
--- a/src/testdir/dumps/Test_pum_highlights_12.dump
+++ b/src/testdir/dumps/Test_pum_highlights_12.dump
@@ -1,7 +1,7 @@
 |a+0&#ffffff0|w|o|r|d|1> @68
-|a+0#ff404010#e0e0e08|w|o|r|d|1| |W| |e|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@52
+|a+0#ff404010#e0e0e08|w|o|r|d|1| +0#0000001&|W| |e|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@52
 |a+0#0000001#ffd7ff255|w|o|r|d|2| |W| |e|x|t|r|a| |t|e|x|t| |2| | +0#4040ff13#ffffff0@52
-|你*0#ff404010#ffd7ff255|好| +&@2|W| |e|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@52
+|你*0#ff404010#ffd7ff255|好| +0#0000001&@2|W| |e|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@52
 |~| @73
 |~| @73
 |~| @73
diff --git a/src/testdir/dumps/Test_pum_highlights_13.dump b/src/testdir/dumps/Test_pum_highlights_13.dump
index 34fde12..96a00eb 100644
--- a/src/testdir/dumps/Test_pum_highlights_13.dump
+++ b/src/testdir/dumps/Test_pum_highlights_13.dump
@@ -1,7 +1,7 @@
 |a+0&#ffffff0|w|o|r|d|1> @68
-|a+8#ff404010#e0e0e08|w|o+0&&|r|d|1| |W| |e|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@52
+|a+8#ff404010#e0e0e08|w|o+0&&|r|d|1| +0#0000001&|W| |e|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@52
 |a+8#0000e05#ffd7ff255|w|o+0#0000001&|r|d|2| |W| |e|x|t|r|a| |t|e|x|t| |2| | +0#4040ff13#ffffff0@52
-|你*0#ff404010#ffd7ff255|好| +&@2|W| |e|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@52
+|你*0#ff404010#ffd7ff255|好| +0#0000001&@2|W| |e|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@52
 |~| @73
 |~| @73
 |~| @73
diff --git a/src/testdir/dumps/Test_pum_highlights_14.dump b/src/testdir/dumps/Test_pum_highlights_14.dump
index f35b4cb..563ee85 100644
--- a/src/testdir/dumps/Test_pum_highlights_14.dump
+++ b/src/testdir/dumps/Test_pum_highlights_14.dump
@@ -1,7 +1,7 @@
 |a+0&#ffffff0|w|o|r|d|2> @68
-|a+8#ff404010#ffd7ff255|w|o+0&&|r|d|1| |W| |e|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@52
+|a+8#ff404010#ffd7ff255|w|o+0&&|r|d|1| +0#0000001&|W| |e|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@52
 |a+8#00e0e07#e0e0e08|w|o+0#0000001&|r|d|2| |W| |e|x|t|r|a| |t|e|x|t| |2| | +0#4040ff13#ffffff0@52
-|你*0#ff404010#ffd7ff255|好| +&@2|W| |e|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@52
+|你*0#ff404010#ffd7ff255|好| +0#0000001&@2|W| |e|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@52
 |~| @73
 |~| @73
 |~| @73
diff --git a/src/testdir/dumps/Test_pum_highlights_16.dump b/src/testdir/dumps/Test_pum_highlights_16.dump
index fe2b68d..5a8d787 100644
--- a/src/testdir/dumps/Test_pum_highlights_16.dump
+++ b/src/testdir/dumps/Test_pum_highlights_16.dump
@@ -1,7 +1,7 @@
 |a+0&#ffffff0|w|o|r|d|1> @68
-|a+0#ff404010#e0e0e08|w|o|r|d|1| |v+0#ffff4012&|a|r|i|a|b|l|e| |e+0#ff404010&|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@45
-|a+0#0000001#ffd7ff255|w|o|r|d|2| |f+0#4040ff13&|u|n|c|t|i|o|n| |e+0#0000001&|x|t|r|a| |t|e|x|t| |2| | +0#4040ff13#ffffff0@45
-|你*0#0000001#ffd7ff255|好| +&@2|c+0#40ff4011&|l|a|s@1| @3|e+0#0000001&|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@45
+|a+0#ff404010#e0e0e08|w|o|r|d|1| +0#0000001&|v+0#ffff4012&|a|r|i|a|b|l|e| +0#0000001&|e|x|t|r|a| |t|e|x|t| |1| | +0#4040ff13#ffffff0@45
+|a+0#0000001#ffd7ff255|w|o|r|d|2| |f+0#4040ff13&|u|n|c|t|i|o|n| +0#0000001&|e|x|t|r|a| |t|e|x|t| |2| | +0#4040ff13#ffffff0@45
+|你*0#0000001#ffd7ff255|好| +&@2|c+0#40ff4011&|l|a|s@1| +0#0000001&@3|e|x|t|r|a| |t|e|x|t| |3| | +0#4040ff13#ffffff0@45
 |~| @73
 |~| @73
 |~| @73
diff --git a/src/testdir/test_popup.vim b/src/testdir/test_popup.vim
index a4f6d02..3c748a4 100644
--- a/src/testdir/test_popup.vim
+++ b/src/testdir/test_popup.vim
@@ -1504,7 +1504,7 @@
   call StopVimInTerminal(buf)
 endfunc
 
-func Test_pum_user_hl_group()
+func Test_pum_user_abbr_hlgroup()
   CheckScreendump
   let lines =<< trim END
     func CompleteFunc( findstart, base )
@@ -1513,9 +1513,9 @@
       endif
       return {
             \ 'words': [
-            \ { 'word': 'aword1', 'menu': 'extra text 1', 'kind': 'W', 'hl_group': 'StrikeFake' },
+            \ { 'word': 'aword1', 'menu': 'extra text 1', 'kind': 'W', 'abbr_hlgroup': 'StrikeFake' },
             \ { 'word': 'aword2', 'menu': 'extra text 2', 'kind': 'W', },
-            \ { 'word': '你好', 'menu': 'extra text 3', 'kind': 'W', 'hl_group': 'StrikeFake' },
+            \ { 'word': '你好', 'menu': 'extra text 3', 'kind': 'W', 'abbr_hlgroup': 'StrikeFake' },
             \]}
     endfunc
     set completeopt=menu
@@ -1557,7 +1557,7 @@
       endif
       return {
             \ 'words': [
-            \ { 'word': 'aword1', 'menu': 'extra text 1', 'kind': 'variable', 'kind_hlgroup': 'KindVar', 'hl_group': 'StrikeFake' },
+            \ { 'word': 'aword1', 'menu': 'extra text 1', 'kind': 'variable', 'kind_hlgroup': 'KindVar', 'abbr_hlgroup': 'StrikeFake' },
             \ { 'word': 'aword2', 'menu': 'extra text 2', 'kind': 'function', 'kind_hlgroup': 'KindFunc' },
             \ { 'word': '你好', 'menu': 'extra text 3', 'kind': 'class', 'kind_hlgroup': 'KindClass'  },
             \]}